The present invention relates generally to articulated arms, and more specifically, to modular hybrid snake arms that are usable with fixed or mobile robotic devices and systems. In particular, this invention may reduce the size and weight of the modular arm segments, which, among other advantages, would allow arms of unusually long length.
A flexible, or snake arm, robot is a computerized electro-mechanical device with many features found in industrial robotic arms. The “snake” description refers to the arm's long cylindrical shape, which can move in ways that are reminiscent of a snake. The flexible snake arm is a robotic “arm” and the most basic technology has been around for several years with snake arms available commercially from several companies. Some snake arms include a fixed base, or platform, possibly even connected to the end of a larger traditional industrial robot arm, with many elements such as ribs or plates connected in series and moved by wires or cables. Typically, the distance between two edges of the rib plates is changed, and when multiplied by many plates, the combined movement causes the arm to move. The elements, ribs or plates are typically actuated by various mechanical mechanisms, such as gears, pistons, cams, and, more typically, by wires or cables.
Some prior arms include U.S. Pat. No. 7,395,606B2, “CMM Arm with Exoskeleton,” (Jul. 8, 2008); U.S. Pat. App. No. 2010/0234985, “Robotic Arm with a Plurality of Articulated Segments,” (Sep. 16, 2010); and U.S. Pat. No. 8,414,246, “Modular Hybrid Snake Arm,” (Apr. 9, 2013).
The present invention improves on the prior art in a number of ways. As a non-limiting example, the preferred embodiment of the system is a modular robotic snake arm wherein each of the snake arm segments derives mechanical power from an articulated drive shaft that passes through the length of the snake arm. In this embodiment, the main source of mechanical power is a motor that remains attached to a base, which causes the articulated drive shaft to rotate. One or more clutch mechanisms in each snake-arm segment harness the rotational power of the articulated drive shaft to alter the orientation of all segments further from the fixed base, as opposed to the ribs or plates of the prior art, which must be actuated independently.